Valve Springs?

[F-BIRD'88]

OP What is the specific camshaft you want to use?
Brand, part # grind #.... valve lash.

Cam card springs recomendation.
What is the max Rpm you want to spin your 400?
Will you add a "rev kit" if needed?

Use a rev limiter ?
The real rocker ratio of your rockers?

Yiur current cam is dead nuts duration and lsa of what I thought you needed on your 400.
I picked you a very close street roller cam with less gross valve lift.. its a custom grind if 106 LSA

You just may be able to get by with a Kmotion K800 set.
Limited rpm..
Alternative Is a 1.525" comp #954 spring
Will a 1.525" dia spring sit in your spring pockets?

Valve length .. Stock? +.100" ? or?
Known valve to piston clearance?

[BTZ201]

Thank you all for your advice and suggestions, I am going to try the competition products complete head improvement kit that comes with 1.5" solid roller springs, valves, seals, locks, retainers.....etc.
I will post when motor is running (could be a while) and how things turn out...
Thanks,
Brent

[af2]

So how much installed height do you currently have available.??? Not including use of a +.050 offset lock??

Exactly!!

There are to many variables without knowing the height.

[BTZ201]

Sorry, didn't see that one. Will not know exact height until my valves, retainers and locks come in. I will measure then.

[ProPower engines]

What length of valve are you using??
Stock length or +.100 longer?? I always go longer to avoid the issue of not enough installed height. Its easier to use a longer valve and spring combo on those heads to avoid the machining of the spring seats.

[F-BIRD'88]

Yes if when a roller cam is planned like the very popular .420" lobe lift which there are tons going +.100" longer valves is just good horse sense on a sbc..
If stock length I like to stay with less than .420" lobe lift cams. Like street roller type stuff.
You can go fast with sub .600" valve lift .
Usually the heads on this stuff don't need super max valvelift.